* {
    margin: 0;
    padding: 0;
}

li {
    list-style: none;
}

a {
    text-decoration: none;
    color: inherit;
}

.header {
    height: 60px;
    padding: 0 20px;
    display: flex;
    align-items: center;
    box-shadow: rgba(0, 0, 0, 0.1) 0 4px 12px;
    /*内容对齐方式为两边对齐*/
    justify-content: space-between;
}

.main {
    width: 1200px;
    /*左右居中*/
    margin: 20px auto;
}

